The problem with using the vanilla tag system for ore dictionary is that tags must exist to be accessed. If you reference a tag that doesnt exist in a recipe it will fail to load. For most things this will only result in console spam but there are cases where it matters.
{
"type": "charcoal_pit:orekiln",
"ingredients": [
[
{
"tag": "forge:ores/copper"
},
{
"tag": "forge:ingots/copper"
},
{
"tag": "forge:dusts/copper"
}
]
],
"result": {
"tag": "forge:ingots/copp